For those still trying to unwrap the riddle inside the mystery that is Russian political culture, there is an instructive moment at the end of Zhmurki - Blind man's buff - the hit gangster film showing in Moscow cinemas this summer.

Set in the blood-soaked underworld of the 1990s, it is the tale of two hired thugs who shoot and torture their way through a series of enemies on the trail of a suitcase full of heroin.

Sergei is the schemer of the two. Simon, his hulking sidekick, sticks to gleefully dispatching opponents using two pistols mounted on rails under his sleeves like Robert de Niro in Taxi Driver.

Yet in the final scene of the film, a remarkable transformation has taken place. It's now 2005, and our anti-heroes - clad in impeccable Armani suits - are lounging in an office overlooking Red Square. Sergei has become an MP.

It says a lot about Russians' expectations of their politicians that a pair of brainless killers can be plausibly reborn as a member of the Duma and his assistant.

That's not to say, of course, that a single member of the current chamber is either an idiot or a murderer. It just illustrates the scepticism with which most Russians view politics, and especially members of parliament.

Similar doubts accompanied the revelation last week that prosecutors have opened an investigation into former prime minister Mikhail Kasyanov for allegedly acquiring a £16m state dacha for a knockdown price.

Kasyanov robustly denies the charge, and his allies perceive a Kremlin plot to warn him off the race for the presidency in 2008, when Vladimir Putin must step down.

Yet the wailing and gnashing of teeth in some western publications made Russians laugh. Few see Kasyanov, with his ties to the family of officials behind Boris Yeltsin's dubious privatisations of the 1990s, as a democratic white knight who will ride in and save the day.

As a rule, presidents themselves, with their wealthy friends and "political technologists", are the sole politicians to avoid such ire.

Once in power, Yeltsin was careful to preserve his popular image as a real "muzhik" - an earthy bloke. Putin's icy calm has its own appeal, and his ratings remain high despite a dip earlier this year when he introduced unpopular welfare reforms.

Both men had the nous to condone a political party rather than joining it, allowing them to step back from unpopular moves in parliament.

That said, there is little doubt that the executive pulls the strings of United Russia, the pro-Putin majority party that acts as a legislative sledgehammer.

In fact, there is every sign that the Kremlin is moving to gain total control of the Duma. The plan is to create a whole series of parties catering to every taste.

Last week, all seemed calm as MPs headed off for their summer recess with plans for fishing trips and berry picking at their dachas. But behind the scenes, the tectonic plates are already moving ahead of the 2007 parliamentary and 2008 presidential elections.

Andrew Wilson, a lecturer at London's School of Slavonic and East European Studies, predicts a "cloning [of] opposition parties to create a Kremlin-controlled imitation of partisan politics" ahead of 2007.

The start of the campaign was signalled last month when Rodina, the nationalist party set up by Putin's allies to split the communist vote during the 2003 parliamentary elections, was broken into two factions.

Thus weakened, it can now be sidelined, or alternatively cultivated as a monstrous threat to persuade voters to choose United Russia.

Meanwhile, United Russia itself - with little ideology besides slavish devotion to Putin (and probably his anointed successor) - looks set to be whipped into a range of enticing parties.

Such machinations are a reminder that political parties here are mainly a platform for presidential ambitions or defenders of business interests, or a little bit of both. And when MPs are caught in the middle of that game, it is little wonder the average Russian doubts their integrity.